Preface xiii Section I Principle and Products Overview of Bioelectrosynthesis 1 1 Principle and Product Overview of Bioelectrosynthesis 3Fang Zhang, Yuquan Wei, and Guanghe Li 1.1 Introduction 3 1.2 Evolution of Bioelectrosynthesis 6 1.3 Fundamental Principles of Bioelectrosynthesis 9 1.4 Plethora of Applications for Chemical Production 11 1.4.1 Hydrogen Production 11 1.4.2 Methane Production 12 1.4.3 Alcohol Production 16 1.4.4 Short-chain Organic Acid Production 17 1.4.5 Ammonia Production and Nitrogen Recovery 23 1.5 Key Factors for Improving MES Performance 26 1.5.1 Electron Transfer from the Cathode to the Cell 26 1.5.2 Cathode Materials 27 1.6 Summary 29 References 29 Section II Biogas Production and Upgrading Technology via Bioelectrolysis 39 2 Hydrogen Production from Waste Stream with Microbial Electrolysis Cells 41Defeng Xing, Yang Yang, Zhen Li, Han Cui, Dongmei Ma, Xiaoyu Cai, and Jiayu Gu 2.1 Construction of MEC and Scale-up 42 2.1.1 Laboratory-Scale MEC 44 2.1.2 Pilot-Scale MEC 46 2.2 Electrode Material of MEC 47 2.2.1 Anode of MEC 47 2.2.2 Cathode of MEC 49 2.2.2.1 Cathode Base Materials in MEC 49 2.2.2.2 Cathode Catalysts in MEC 49 2.2.2.3 Biological Catalysts in MEC 51 2.3 Effect of Operation Conditions on Hydrogen Production 51 2.3.1 Effect of Substrate on Hydrogen Production 51 2.3.2 Effects of Applied Voltage and Magnetic Field on Hydrogen Production 52 2.3.3 Effect of pH on Hydrogen Production 54 2.3.4 Effect of Temperature on Hydrogen Production 54 2.4 Electroactive Biofilm Microbiome and Syntrophic Interaction in MEC 54 2.4.1 Anodic EAM and Biofilm Formation 55 2.4.2 EAM in the Cathode 56 2.4.3 Microbial Community and Syntrophic Interaction 58 2.4.3.1 Pure Culture and Mixed Culture 58 2.4.3.2 Microbiome in Electroactive Biofilms 58 2.4.3.3 Suppressing the Methanogens 59 2.5 Coupled System for Biohydrogen Production 60 2.5.1 MEC-MFC-Coupled System for Biohydrogen Production 60 2.5.2 AD-MEC-Coupled System for Hydrogen Production 60 2.5.3 Solar-Powered MEC-Coupled System for Hydrogen Production 61 2.5.4 Other Modified MEC System for Hydrogen Production 61 2.6 Challenges and Outlook 62 Acknowledgment 63 References 64 3 A Promising Strategy for Renewable Energy Recovery: Conversion of OrganicWastes to Methane via Electromethanogenesis 71Zhiqiang Zhao and Yaobin Zhang 3.1 Introduction 71 3.2 Advances in Electromethanogenesis 72 3.3 Mechanisms of Electromethanogenesis 75 3.3.1 Electron Transfer from Electrode to Methanogens 75 3.3.2 Microbial Communities of Biocathode 77 3.4 Applications of Electromethanogenesis 81 3.4.1 Renewable Energy Storage 81 3.4.2 Biogas Upgrading 82 3.4.3 Organic Waste Treatment 83 3.5 Outlook 86 References 87 4 Microbial Electrolysis Cell (MEC): An Innovative Waste to Bioenergy and Value-Added By-product Technology 95Abudukeremu Kadier, Najeeb K. N. Al-Shorgani, Dipak A. Jadhav, Jayesh M. Sonawane, Abhilasha S.Mathuriya,Mohd S. Kalil, Hassimi A. Hasan, and Khulood Fahad Saud Alabbosh 4.1 Introduction 95 4.2 Microbial Electrolysis Cell (MEC) for Hydrogen Production and Waste Treatment 96 4.2.1 Working Principles 96 4.2.2 Advantages of MEC Over Other Potential Waste Treatment Technologies 97 4.3 Different Types of Waste Feedstocks Used in MECs 99 4.3.1 Simple or Defined Substrates 99 4.3.1.1 Glucose 106 4.3.1.2 Acetate 106 4.3.1.3 Glycerol 106 4.3.1.4 Proteins 107 4.3.1.5 Volatile Fatty Acids (VFAs) 107 4.3.1.6 DF Effluents and Other Pure Substrates 108 4.3.2 Wastewater Feedstocks 108 4.3.2.1 Domestic Wastewater (DW) 108 4.3.2.2 Industrial Wastewater 109 4.3.3 Complex or Lignocellulosic Biomass Materials 110 4.3.4 Waste-Activated Sludge (WAS) 110 4.3.5 Agricultural Wastes and Landfill Leachate 113 4.4 Current Applications of MEC 113 4.4.1 Hydrogen Production and Ammonium Recovery from Urine 113 4.4.2 Metal Removal or Recovery from Wastes 115 4.5 Existing Challenges and Bottlenecks for the Use of Wastewaters as Substrates in MECs 117 4.6 Conclusion and Future Outlook 118 Acknowledgments 119 References 119 5 Methane Production at Biocathodes: Principles and Applications 129Dandan Liu,Marco Zeppilli, Marianna Villano, Cees Buisman, and Annemiek ter Heijne 5.1 Introduction 129 5.2 Fundamentals of Methane-Producing Biocathode 131 5.2.1 Cathode Potential and Mechanism of Methane Production 133 5.2.2 Methane Production Rate 135 5.2.3 Current-to-Methane, Voltage, and Energy Efficiencies 136 5.2.4 Electron Donor for Methane-Producing BESs 138 5.3 Enhancing Methane Production Rates in AD 139 5.3.1 AD+BES Combination 139 5.3.2 BES +AD Combination 143 5.3.3 BESWithin AD Combination 143 5.4 Upgrading of Biogas 145 5.4.1 Fundamental Aspects of Biogas Upgrading 145 5.4.2 Alkalinity Generation in BES Biocathodes and CO2 Removal 147 5.5 Storage of Renewable Energy Through Methane-Producing Bioelectrochemical System 150 5.6 Conclusions and Outlook 153 References 154 Section III Organic Production in Microbial Electrosynthesis System 161 6 Organic Synthesis on Cathodes 163AnnieModestra Jampala, Sai K. Butti, and Srinivasulu Reddy VenkataMohan 6.1 Carbon Reduction for Organics Synthesis at Cathode 163 6.1.1 Gas Fermentation 164 6.1.2 Microbial Electrosynthesis (MES) 165 6.2 Acetate Synthesis 168 6.2.1 Biochemistry of Acetate Synthesis 168 6.2.2 Bacteria for Acetate Synthesis 171 6.3 Formic acid Synthesis 171 6.3.1 Direct and Indirect Conversion 172 6.3.2 Production Yields and Optimizations 172 6.4 Alcohol Synthesis 174 6.5 Conclusions and Future Outlook 175 Acknowledgments 176 References 176 Section IV Chemical Products and Nitrogen Recovery 183 7 Inorganic Compound Synthesis in Bioelectrochemical System: Generation Rate Increase and Application 185Lei Gao, Xi-Qi Li, Ling Wang,Wen-Zong Liu, and Ai-Jie Wang 7.1 Introduction 185 7.2 Hydrogen Peroxide Produced in BES: Optimization and Application 186 7.2.1 Electrode Optimization Design 188 7.2.2 Membrane Material Selection 189 7.2.2.1 Cation Exchange Membrane 192 7.2.2.2 Anion Exchange Membrane 193 7.2.2.3 Other Common Membranes 193 7.2.3 Operation Condition Optimization 194 7.2.3.1 Buffer Solution 194 7.2.3.2 Hydraulic Retention Time 195 7.2.3.3 Applied Voltage 195 7.2.4 Application of H2O2 Production in BES 196 7.2.5 Summary 197 7.3 Metal Ion Reduction in BES: Waste Treatment and Metal Reuse 197 7.3.1 Metal Waste Treatment 197 7.3.2 Metal Reuse 198 7.3.3 Summary 199 7.4 Struvite Crystallization Recovery: Principle and Application in BES Systems 199 7.4.1 Principle of Struvite Crystallization Recovery 200 7.4.2 Struvite Crystal Recovery Applied in MFC 200 7.4.3 Struvite Crystal Recovery Applied in MEC 201 7.4.4 Summary 201 7.5 Ammonia Recovery and Other Inorganics Synthesis in BES Systems 202 7.5.1 Migration of NH4 + in BES Systems 202 7.5.2 Ammonia Recovery in BES Systems 202 7.5.3 Other Inorganics Synthesis in BES Systems 203 7.5.4 Summary 205 7.6 Outlook 205 Acknowledgments 206 References 206 8 Bioelectrochemical Ammonium Production - Nitrogen Removal and Recovery in BES 217Guoqiang Zhan 8.1 Ammonium Migration and Recovery 218 8.2 Anodic Ammonium Oxidation 220 8.3 Nitrification/Denitrification in BESs 224 8.4 Existing Problems and Challenges 227 References 227 9 Bioelectrochemical Systems for Heavy Metal Pollution Control and Resource Recovery 233Bo Zhang, Wentao Jiao, and Heming Wang 9.1 Introduction 233 9.1.1 Brief Review of Commonly Used Technologies for Heavy Metal Pollution Control and Their Respective Limitations 233 9.1.2 Control of Heavy Metal Pollution Through (Bio)Electrochemical Processes 234 9.2 BES and its Application in Heavy Metal Pollution Control 236 9.2.1 Configuration of BES 236 9.2.2 BES Application in Treating Heavy Metal Laden Wastewater 238 9.2.2.1 BES with Abiotic Cathode 238 9.2.2.2 BES with Biocathode 244 9.2.3 BES Application in Controlling Heavy Metal Polluted Soils 246 9.3 Outlook and Concluding Remarks 247 Acknowledgments 248 References 248 Section V External Electron Transfer and Electrode Material Promotion 255 10 External Electron Transfer and Electrode Material Promotion 257Fanghua Liu, Hengduo Xu, and Jiajia Li 10.1 External Electron Transfer 258 10.1.1 Direct Electron Transfer 259 10.1.2 Indirect Electron Transfer 260 10.2 Promotion of Material Development 262 10.2.1 Carbon-Based Electrodes for Bioelectrosynthesis 263 10.2.2 Metal-Based Electrode for Bioelectrosynthesis 264 10.3 Modified Electrodes for High Bioelectrosynthesis 265 10.3.1 Electrode Modification with Carbon-Based Materials 265 10.3.1.1 Carbon Nanotube 265 10.3.1.2 Graphene 266 10.3.1.3 Activated Carbon 269 10.3.2 Electrode Decoration with Metal-Based Materials 269 10.3.3 Electrode Decoration with Other Materials 270 10.4 Interspecies Electron Transfer Pathway 272 10.5 Future Perspectives 273 References 274 11 External Electron Transfer: Pathway, Mechanism, and Microorganisms Involved 281Cong Huang, Jun Nan, and Aijie Wang 11.1 External Electron Transfer of Cathode 281 11.1.1 Interspecies Electron Transfer (IET) 282 11.1.2 Direct Electron Transfer (DET) 283 11.2 Promotion of Material Development 284 11.3 Interspecies Electron Transfer Pathway 287 11.3.1 Mechanism of MIET 289 11.3.2 Mechanism of DIET 289 11.3.3 IET Microorganisms 290 References 290 12 Extracellular Electron Transport of Electroactive Biofilm 295Xu Zhang 12.1 Electroactive Bacteria 295 12.1.1 Role of Multiheme Cytochromes in Extracellular Electron Transport (EET) 295 12.2 Electron Transport Across Geobacter( Dominated) EABs 297 12.2.1 "Metallic-like" Conductivity via Microbial Nanowires 297 12.2.2 Redox Conduction 298 12.2.3 Basic Electrochemical Characterization of Redox Conductors 300 References 302 Section VI TheMicrobiology of Bioelectrosynthesis 307 13 Microbial Growth and Ecological and Metabolic Characteristics in Bioelectrosynthesis Systems 309Qian Liu and Sihao Lv 13.1 Microbial Growth Kinetics and Energetics 309 13.1.1 Stoichiometry of Microbial Growth Systems 309 13.1.2 Electrode-Respiring Bacteria Kinetics 312 13.1.3 MES-Associated Carbon Fixation Pathways 315 13.1.3.1 Wood-Ljungdahl Pathway 315 13.1.3.2 Reverse Tricarboxylic Acid Cycle 316 13.1.3.3 3-Hydreoxypropionate/4-Hydroxybutyrate Pathway 316 13.1.3.4 Calvin-Benson-Bassham Cycle 317 13.1.4 Bacterial Energetics 317 13.2 Microbial Ecological Characterization and Biofilm-Related Aspects 318 13.2.1 Model Electroactive Microorganisms 318 13.2.2 Electroactive Microorganism's Ecology Characteristics 319 13.2.2.1 Environmental Characteristics 319 13.2.2.2 Metabolic Characteristics 320 13.2.3 Microbial Biofilm Formation and Characteristics 320 13.2.3.1 Electron-Release Anodic Biofilms 320 13.2.3.2 Cathodic Biofilm for Hydrogen Production 321 13.2.3.3 Cathodic Biofilm for Methane Production 321 13.2.3.4 Cathodic Biofilm for Organic Acid Production 321 13.2.4 Meta-omics Characterization 322 13.2.4.1 Metagenomics of MES-Associated Microorganisms 322 13.2.4.2 Metatranscriptomics of MES-Associated Microorganisms 322 13.3 Influence of Bioelectrochemistry on Microbial Community and Metabolism Pathway 323 13.3.1 Influence of Bioelectrochemistry on Microbial Community 323 13.3.2 Effects of Electrochemistry on Microbial Activity 324 13.3.3 Influence of Bioelectrochemistry on Microbial Metabolism Pathway 324 References 325 14 An Update Perspective of Electron Transfer in Electrosyntrophic Methanogenesis: From VFAs to Methane 333Weiwei Cai, Linna Cai, and Hong Yao 14.1 Introduction 333 14.2 Interspecies Hydrogen/Formate Electron Transfer and Transport/Flow in Methanogens 333 14.3 Beyond Hydrogen/Formate Electron Carriers 336 14.3.1 Direct Interspecies Electron Transfer for Acetotrophic Methanogens 336 14.3.2 Novel Electron Donor for Hydrogenotrophic Methanogens 337 14.4 Power Drives Interspecies Electron Transfer (Kinetics and Energetics) 339 14.5 Multi-VFA Degradation Disturbance by Electrosyntrophic DIET 343 14.5.1 Mechanism of the Methanogenic Degradation of VFAs 344 14.5.1.1 Process of Anaerobic Digestion in an Electrochemical System 344 14.5.1.2 Conversion of Propionate and Acetate 346 14.5.1.3 Conversion of Butyrate and Acetate 347 14.5.1.4 Conversion of Formate and Acetate 348 14.5.1.5 Conversion of Valerate 349 14.5.1.6 Conversion of Mixed-VFAs vs. Individual VFA 350 14.5.2 DIET Process During the Methanogenesis 350 14.6 Overview of Application 352 14.7 Direct Electron Transfer in Methane Oxidation 353 14.8 Challenges 353 14.8.1 Electron Transfer Across the Bridge Between Electrode and Cell 353 14.8.2 Mechanism of Cytoplasmic Reactions 354 14.9 Conclusion 354 Acknowledgment 354 References 355 15 Microbial Metabolism Kinetics and Interactions in Bioelectrosynthesis System 363Zechong Guo and Chunxue Yang 15.1 Introduction 363 15.2 Microbial Metabolism Kinetics of Anode 366 15.2.1 Dynamic Description of Anodic Processes 366 15.2.2 Influencing Factors for Anodic Kinetics 371 15.2.3 Anode Potential Losses 372 15.3 Electrosynthesis Kinetics of Cathode 374 15.3.1 Dynamic Description of Cathode Electrosynthesis Processes 374 15.3.2 Cathode Potential Losses 376 15.4 Energy Balance in Bioelectrosynthesis Systems 378 15.4.1 Energy Transfer and Dissipation 378 15.4.2 Electron Balance in Electronic Circuit 380 15.4.3 Energy Recovery Efficiency Evaluation 383 15.5 Microbial Community Growth on Electrode 384 15.5.1 Anode Biofilm Formation Determined by Anode Potentials 384 15.5.2 Anodic Biofilm Structure 386 15.5.3 Interaction of Functional Communities in Integrated System of Bioelectrochemistry and Anaerobic Digestion 388 References 391 Index 395